问题补充:
单选题Thechildenjoyed_____upthewoodenbricksthenknockingthemdown.A.addingB.pushingC.pilingD.forming
答案:
C解析pile up (=lay in a pile or as if in a pile)把......放成一堆, 堆积:pile up the books on the table (把书堆在桌子上)。Pile up作不及物动词用, 意为“积压; (若干汽车)相撞”:1) Perishable goods are piling up at the docks. (码头上易腐烂的货物堆积如山。) 2) Several cars piled up after ignoring the fog warning on the motorway. (由于无视高速公路上的大雾警告, 有好几辆汽车相撞。)